Defensive publication

ABSTRACT

THE PRESSURE SENSITIVITY OF A COLOR DIFFUSION TRANSFER SYSTEM EMPLOYING DIRECT-POSITIVE, SILVER HALIDE EMULSIONS IS REDUCED BY ADDING TO AT LEAST ONE OF THE SILVER HALIDE EMULSION LAYERS PRIOR TO COATING, A DISPERSION OF A SUBSTANTIALLY WATER-INSOLUBLE, HIGH BOILING, NONPOLYMERIC MATERIAL GENERALLY KNOWN AS A COUPLER SOLVENT IN A HYDROPHILIC COLLOID SUCH AS GELATIN. THE DYE IMAGE-PROVIDING MATERIAL IS PREFERABLY A &#34;FISCHER-TYPE&#34; NONDIFFUSIBLE COUPLER HAVING AN ACIDIC SOLUBILIZING GROUP THEREON SUCH AS A SULFONIC ACID GROUP, THE COUPLER BEING CAPABLE OF REACTING WITH OXIDIZED AROMATIC PRIMARY AMINO COLOR DEVELOPING AGENT TO PRODUCE A DIFFUSIBLE DYE. THE DIRECTPOSITIVE, SILVER HALIDE EMULSION IS PREFERABLY AN INTERNALIMAGE EMULSION WHEREIN THE SILVER HALIDE FORMS LATENT IMAGES PREDOMINANTLY INSIDE THE SILVER HALIDE GRAINS. THE NONPLYMERIC SOLVENT HAS A BOILING POINT ABOVE ABOUT 175*C, AND IS PRESENT AT A CONCENTRATION OF FROM ABOUT 5 TO ABOUT 150 MG. PER SQUARE FOOT OF PHOTOSENSITIVE ELEMENT. EXAMPLES OF SUCH MATERIALS INCLUDE TRICRESYL PHOSPHATE, N-BUTYL PHTHALATE AND ETHYL-N,N-DI-N-BUTYL CARBAMATE. A REDUCTION IN PRESSURE SENSITIVITY OF THE PHOTOSENSITIVE ELEMENT ENABLES IT TO BE SUBJECTED TO STRESS CONDITIONS IN A CAMERA SUCH AS MAKING A 180* DIRECTION CHANGE OVER A SMALL ROLLER WITHOUT LOSS OF SPEED OR MAXIMUM DYE DENSITIES.



